Association of Socioeconomic Status With Dementia Diagnosis Among Older Adults in Denmark

Association of aortic valve calcium with dementia and stroke: The Multi-Ethnic Study of Atherosclerosis

BACKGROUND AND AIMS

Calcific aortic valve disease is associated with increased thrombin formation, platelet activation, decreased fibrinolysis, and subclinical brain infarcts. We examined the long-term association of aortic valve calcification (AVC) with newly diagnosed dementia and incident stroke in the Multi-Ethnic Study of Atherosclerosis (MESA).

METHODS

AVC was measured using non-contrast cardiac CT at Visit 1. We examined AVC as a continuous (log-transformed) and categorical variable (0, 1-99, 100-299, ≥300). Newly diagnosed dementia was adjudicated using International Classification of Disease codes. Stroke was adjudicated from medical records. We calculated absolute event rates (per 1000 person-years) and multivariable adjusted Cox proportional hazards ratios (HR).

RESULTS

Overall, 6812 participants had AVC quantified with a mean age of 62.1 years old, 52.9 % were women, and the median 10-year estimated atherosclerotic cardiovascular disease (ASCVD) risk was 13.5 %. Participants with AVC >0 were older and less likely to be women compared to those with AVC=0. Over a median 16-year follow-up, there were 535 cases of dementia and 376 cases of stroke. The absolute risk of newly diagnosed dementia increased in a stepwise pattern with higher AVC scores, and stroke increased in a logarithmic pattern. In multivariable analyses, AVC was significantly associated with newly diagnosed dementia as a log-transformed continuous variable (HR 1.09; 95 % CI 1.04-1.14) and persons with AVC ≥300 had nearly a two-fold higher risk (HR 1.77; 95 % CI 1.14-2.76) compared to those with AVC=0. AVC was associated with an increased risk of stroke after adjustment for age, sex, and race/ethnicity, but not after adjustment for ASCVD risk factors.

CONCLUSIONS

After multivariable adjustment, AVC >0 was significantly associated with an increased risk of newly diagnosed dementia, but not incident stroke. This suggests that AVC may be an important risk factor for the long-term risk of dementia beyond traditional ASCVD risk factors.

Identifying the mediating role of inflammation on the relationship between socioeconomic status and Alzheimer's disease: a Mendelian randomization analysis and mediation analysis

BACKGROUND AND OBJECTIVES

Observational studies have demonstrated a significant association between socio-economic status (SES) and Alzheimer's disease (AD). Nonetheless, the precise biological mechanisms underlying this association remain unclear. Therefore, we adopted a Mendelian Randomization (MR) approach to investigate the causal relationship between SES and genetic susceptibility to AD, as well as to explore the potential mediation effects of inflammation.

METHODS

Large-scale cohorts based on publicly available genome-wide association study (GWAS) datasets from European populations were employed for conducting the MR study. The primary criterion utilized was the inverse-variance weighting (IVW) model. Heterogeneity and horizontal pleiotropy were assessed. In addition, multivariate MR (MVMR) was utilized to correct the confounders. Moreover, a two-step MR approach was used to evaluate the potential mediating effects of factors on the causal effects between SES and AD.

RESULTS

As indicated by the results of the IVW model, educational years (OR = 0.708, 95% CI 0.610-0.821, P < 0.001) and household income (OR = 0.746, 95% CI 0.566-0.982, P = 0.037) was associated with a decreased genetic susceptibility risk for AD. The univariable results showed that the causal effect of educational years on the lower risk of AD remained significant (OR = 0.643, 95% CI 0.467-0.886, P = 0.006). In addition, our findings indicated that C-reactive protein (CRP) played a role in the causal effect of educational years on AD. The proportions of mediation were - 50.08% (95% CI - 92.78; - 7.38%).

DISCUSSION

These findings provided evidence supporting the causal effect of educational attainment lower AD risk, with inflammation playing a mediating role. These findings may inform prevention strategies and interventions directed toward AD. Future studies should explore other plausible biological mechanisms.

Considering inequities in national dementia strategies: breadth, depth, and scope

BACKGROUND

Considering that dementia is an international public health priority, several countries have developed national dementia strategies outlining initiatives to address challenges posed by the disease. These strategies aim to improve the care, support, and resources available to meet the needs of persons living with dementia and their care partners and communities. Despite the known impact of social determinants of health on dementia risk, care, and outcomes, it is unclear whether dementia strategies adequately address related inequities. This study aimed to describe whether and how national dementia strategies considered inequities associated with social determinants of health.

METHODS

We conducted an environmental scan of the national dementia strategies of countries that are part of the Organisation for Economic Cooperation and Development (OECD). Included strategies had to be accessible in English or French. Sub-national or provincial plans were excluded. We synthesised information on strategies' considerations of inequity through a thematic analysis.

RESULTS

Of the 15 dementia strategies that met inclusion criteria, 13 mentioned at least one inequity (M = 2.4, median = 2, range:0-7) related to Race/Ethnicity; Religion; Age; Disability; Sexual Orientation/Gender Identity; Social Class; or Rurality. Age and disability were mentioned most frequently, and religion most infrequently. Eleven strategies included general inequity-focused objectives, while only 5 had specific inequity-focused objectives in the form of tangible percentage changes, deadlines, or allocated budgets for achieving equity-related goals outlined in their strategies.

CONCLUSIONS

Understanding if and how countries consider inequities in their dementia strategies enables the development of future strategies that adequately target inequities of concern. While most of the strategies mentioned inequities, few included tangible objectives to reduce them. Countries must not only consider inequities at a surface-level; rather, they must put forth actionable objectives that intend to lessen the impact of inequities in the care of all persons living with dementia.

The impact of poverty and socioeconomic status on brain, behaviour, and development: a unified framework

In this article, we, for the first time, provide a comprehensive overview and unified framework of the impact of poverty and low socioeconomic status (SES) on the brain and behaviour. While there are many studies on the impact of low SES on the brain (including cortex, hippocampus, amygdala, and even neurotransmitters) and behaviours (including educational attainment, language development, development of psychopathological disorders), prior studies did not integrate behavioural, educational, and neural findings in one framework. Here, we argue that the impact of poverty and low SES on the brain and behaviour are interrelated. Specifically, based on prior studies, due to a lack of resources, poverty and low SES are associated with poor nutrition, high levels of stress in caregivers and their children, and exposure to socio-environmental hazards. These psychological and physical injuries impact the normal development of several brain areas and neurotransmitters. Impaired functioning of the amygdala can lead to the development of psychopathological disorders, while impaired hippocampus and cortex functions are associated with a delay in learning and language development as well as poor academic performance. This in turn perpetuates poverty in children, leading to a vicious cycle of poverty and psychological/physical impairments. In addition to providing economic aid to economically disadvantaged families, interventions should aim to tackle neural abnormalities caused by poverty and low SES in early childhood. Importantly, acknowledging brain abnormalities due to poverty in early childhood can help increase economic equity. In the current study, we provide a comprehensive list of future studies to help understand the impact of poverty on the brain.

Associations of environmental factors with neurodegeneration: An exposome-wide Mendelian randomization investigation

Neurodegenerative diseases (NDDs) remain a global health challenge. Previous studies have reported potential links between environmental factors and NDDs, however, findings remain controversial across studies and elusive to be interpreted as evidence of robust causal associations. In this study, we comprehensively explored the causal associations of the common environmental factors with major NDDs including Alzheimer's disease (AD), Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), and multiple sclerosis (MS), based on updated large-scale genome-wide association study data through two-sample Mendelian randomization (MR) approach. Our results indicated that, overall, 28 significant sets of exposure-outcome causal association evidence were detected, 12 of which were previously underestimated and newly identified, including average weekly beer plus cider intake, strenuous sports or other exercises, diastolic blood pressure, and body fat percentage with AD, alcohol intake frequency with PD, apolipoprotein B, systolic blood pressure, and forced expiratory volume in 1 s (FEV1) with ALS, and alcohol intake frequency, hip circumference, forced vital capacity, and FEV1 with MS. Moreover, the causal effects of several environmental factors on NDDs were found to overlap. From a triangulation perspective, our investigation provided insights into understanding the associations of environmental factors with NDDs, providing causality-oriented evidence to establish the risk profile of NDDs.

Healthcare use according to deprivation among French Alzheimer's Disease and Related Diseases subjects: a national cross-sectional descriptive study based on the FRA-DEM cohort

Introduction

Pluriprofessional and coordinated healthcare use is recommended for Alzheimer's Disease and Related Diseases (ADRD). Despite a protective health system, France is characterized by persistent and significant social inequalities in health. Although social health inequalities are well documented, less is known about social disparities in healthcare use in ADRD, especially in France. Therefore, this study aimed to describe healthcare use according to socioeconomic deprivation among ADRD subjects and the possible potentiating role of deprivation by age.

Methods

We studied subjects identified with incident ADRD in 2017 in the French health insurance database (SNDS). We described a large extent of their healthcare use during the year following their ADRD identification. Deprivation was assessed through French deprivation index (Fdep), measured at the municipality level, and categorized into quintiles. We compared healthcare use according to the Fdep quintiles through chi-square tests. We stratified the description of certain healthcare uses by age groups (40-64 years, 65-74 years, 75-84 years, 85 years, and older), number of comorbidities (0, 1, 2-3, 4 comorbidities and more), or the presence of psychiatric comorbidity.

Results

In total, 124,441 subjects were included. The most deprived subjects had less use of physiotherapy (28.56% vs. 38.24%), ambulatory specialists (27.24% vs. 34.07%), ambulatory speech therapy (6.35% vs. 16.64%), preventive consultations (62.34% vs. 69.65%), and were less institutionalized (28.09% vs. 31.33%) than the less deprived ones. Conversely, they were more exposed to antipsychotics (11.16% vs. 8.43%), benzodiazepines (24.34% vs. 19.07%), hospital emergency care (63.84% vs. 57.57%), and potentially avoidable hospitalizations (12.04% vs. 10.95%) than the less deprived ones.

Discussion and conclusion

The healthcare use of subjects with ADRD in France differed according to the deprivation index, suggesting potential health renunciation as in other diseases. These social inequalities may be driven by financial barriers and lower education levels, which contribute to health literacy (especially for preventive care). Further studies may explore them.

Leading determinants of incident dementia among individuals with and without the apolipoprotein E ε4 genotype: a retrospective cohort study

BACKGROUND

Little is known regarding the leading risk factors for dementia/Alzheimer's disease (AD) in individuals with and without APOE4. The identification of key risk factors for dementia/Alzheimer's disease (AD) in individuals with and without the APOE4 gene is of significant importance in global health.

METHODS

Our analysis included 110,354 APOE4 carriers and 220,708 age- and sex-matched controls aged 40-73 years at baseline (between 2006-2010) from UK Biobank. Incident dementia was ascertained using hospital inpatient, or death records until January 2021. Individuals of non-European ancestry were excluded. Furthermore, individuals without medical record linkage were excluded from the analysis. Moderation analysis was tested for 134 individual factors.

RESULTS

During a median follow-up of 11.9 years, 4,764 cases of incident all-cause dementia and 2065 incident AD cases were documented. Hazard ratios (95% CIs) for all-cause dementia and AD associated with APOE4 were 2.70(2.55-2.85) and 3.72(3.40-4.07), respectively. In APOE4 carriers, the leading risk factors for all-cause dementia included low self-rated overall health, low household income, high multimorbidity risk score, long-term illness, high neutrophil percentage, and high nitrogen dioxide air pollution. In non-APOE4 carriers, the leading risk factors included high multimorbidity risk score, low overall self-rated health, low household income, long-term illness, high microalbumin in urine, high neutrophil count, and low greenspace percentage. Population attributable risk for these individual risk factors combined was 65.1%, and 85.8% in APOE4 and non-APOE4 carriers, respectively. For 20 risk factors including multimorbidity risk score, unhealthy lifestyle habits, and particulate matter air pollutants, their associations with incident dementia were stronger in non-APOE4 carriers. For only 2 risk factors (mother's history of dementia, low C-reactive protein), their associations with incident all-cause dementia were stronger in APOE4 carriers.

CONCLUSIONS

Our findings provide evidence for personalized preventative approaches to dementia/AD in APOE4 and non-APOE4 carriers. A mother's history of dementia and low levels of C-reactive protein were more important risk factors of dementia in APOE4 carriers whereas leading risk factors including unhealthy lifestyle habits, multimorbidity risk score, inflammation and immune-related markers were more predictive of dementia in non-APOE4 carriers.

Racial and Ethnic Differences in the Population-Attributable Fractions of Alzheimer Disease and Related Dementias

BACKGROUND AND OBJECTIVES

Previous studies estimated that modifiable risk factors explain up to 40% of the dementia cases in the United States and that this population-attributable fraction (PAF) differs by race and ethnicity-estimates of future impact based on the risk factor prevalence in contemporary surveys. The aim of this study was to determine the race-specific and ethnicity-specific PAF of late-onset Alzheimer disease and related dementias (ADRDs) based on the risk factor prevalence and associations observed on the same individuals within a prospective cohort.

METHODS

Data were from Multiethnic Cohort Study participants (African American, Japanese American, Latino, Native Hawaiian, and White) enrolled in Medicare Fee-for-Service. We estimated the PAF based on the prevalence of risk factors at cohort baseline and their mutually adjusted association with subsequent ADRD incidence. Risk factors included low educational attainment and midlife exposures to low neighborhood socioeconomic status, unmarried status, history of hypertension, stroke, diabetes or heart disease, smoking, physical inactivity, short or long sleep duration, obesity, and low-quality diet, as well as APOE ε4 for a subset.

RESULTS

Among 91,881 participants (mean age 59.3 at baseline, 55.0% female participants), 16,507 incident ADRD cases were identified from Medicare claims (1999-2016, mean follow-up 9.3 years). The PAF for nongenetic factors combined was similar in men (24.0% [95% CI 21.3-26.6]) and women (22.8% [20.3-25.2]) but varied across Japanese American (14.2% [11.1-17.2]), White (21.9% [19.0-24.7]), African American (27.8% [22.3-33.0]), Native Hawaiian (29.3% [21.0-36.7]), and Latino (33.3% [27.5-38.5]) groups. The combined PAF was attenuated when accounting for competing risk of death, in both men (10.4%) and women (13.9%) and across racial and ethnic groups (4.7%-25.5%). The combined PAF was also different by age at diagnosis and ADRD subtypes, higher for younger (65-74 years: 43.2%) than older (75-84 years: 32.4%; ≥85 years: 11.3%) diagnoses and higher for vascular or unspecified ADRD than for AD or Lewy body dementia. An additional PAF of 11.8% (9.9-13.6) was associated with APOE ε4, which together with nongenetic risk factors accounted for 30.6% (25.8-35.1) of ADRD.

DISCUSSION

Known risk factors explained about a third of the ADRD cases but with unequal distributions across racial and ethnic groups.

Impact of prescribed opioid use on development of dementia among patients with chronic non-cancer pain

We aimed to examine the association between opioid use and the development of dementia in patients with chronic non-cancer pain in South Korea. Data were extracted from the National Health Insurance Service database in South Korea. Adult patients diagnosed with musculoskeletal diseases with chronic non-cancer pain between 2010 and 2015 were included in the analysis. Patients who were prescribed opioids regularly and continuously for ≥ 90 days were classified as opioid users. In total, 1,261,682 patients with chronic non-cancer pain were included in the final analysis, of whom 21,800 (1.7%) were opioid users. From January 1, 2016 to December 31, 2020, 35,239 (2.8%) patients with chronic non-cancer pain were newly diagnosed with dementia. In the multivariable model, opioid users showed a 15% higher risk of developing dementia than the control group. Additionally, opioid users showed a 15% and 16% higher risk of developing Alzheimer's disease and unspecified dementia, respectively, than the control group, but did not show any significant differences for vascular dementia. Among adult patients with chronic non-cancer pain, opioid users were at a higher risk of developing dementia than the control group; the risk was significantly higher for Alzheimer's disease but not for vascular dementia in this study. Our results suggest that in patients with CNCP, public health strategies should target opioid users for early dementia detection and intervention.

Dental decision-making for persons with dementia: A systematic narrative review

Dental decision-making represents the establishment of a common understanding between the dental professional and the recipient of the intervention, which determines oral healthcare and dental treatment policies. Dental decision-making for persons with dementia can be challenging, and there have been no systematic reviews on this topic. Therefore, this systematic narrative review aimed to identify the current state of dental decision-making in persons with dementia. Literature search was performed using PubMed, Web of Science, Cochrane Library, CINAHL, and Google Scholar databases. Through the process of research selection, 7 articles with a high risk of bias were included in this study. This review clarified that there is limited information on the dental decision-making processes for persons with dementia. In conclusion, although this may be difficult due to different medical and socioeconomic conditions, the dilemma between the need to establish evidence for dental decision-making and medical ethics that prioritize a patient-centered position should be discussed globally in the future.

Unlocking the Protective Potential of Upper Respiratory Infection Treatment Histories against Alzheimer's Disease: A Korean Adult Population Study

With increasing interest in the inflammation-pathogen infection hypothesis and its potential links to Alzheimer's disease (AD) development, there is growing consideration of using upper respiratory infection (URI) treatments as interventions for AD. This nested case-control study explored the potential association between prior URI histories and AD development in a Korean adult population using the national health screening cohort data (2002-2019). The study included 26,920 AD patients and 107,680 matched control individuals, focusing on those seeking respiratory treatment. Logistic regression analyses assessed the impact of URI histories and treatment on AD risk while adjusting for covariates. Our results revealed that over a 1-year period, individuals with URI histories (≥1, ≥2, or ≥3 instances) exhibited decreasing probabilities of developing AD, with risk reductions of 19%, 15%, and 12%, respectively. Expanding our investigation to a 2-year period consistently showed a 17% reduction in AD risk. This effect remained robust across diverse demographic groups and after adjusting for covariates, encompassing comorbidities, hypertension, hyperlipidemia, blood glucose levels, and lifestyle factors. Subgroup analyses further substantiated this association. In conclusion, our findings cautiously suggest a potential protective role of prior URI treatment histories in mitigating the risk of AD development.

Androgen deprivation therapy for prostate cancer and neurocognitive disorders: a systematic review and meta-analysis

BACKGROUND

Prostate cancer is a prevalent disease that urgently needs to address its treatment-related complications. By examining existing evidence on the association between Androgen Deprivation Therapy (ADT) and dementia, this study contributes to the understanding of potential risks. We sought to analyze the currently available evidence regarding the risk of dementia, Alzheimer's disease (AD), vascular dementia, and Parkinson's disease (PD) in patients undergoing ADT.

METHODS

A systematic search of PubMed, EMBASE, Scopus, and Google Scholar was performed to identify studies published from the databases' inception to April 2023. Studies were identified through systematic review to facilitate comparisons between studies with and without some degree of controls for biases affecting distinctions between ADT receivers and non-ADT receivers. This review identified 305 studies, with 28 meeting the inclusion criteria. Heterogeneity was assessed using Higgins I2%. Variables with an I2 over 50% were considered heterogeneous and analyzed using a Random-Effects model. Otherwise, a Fixed-Effects model was employed.

RESULTS

A total of 28 studies were included for analysis. Out of these, only 1 study did not report the number of patients. From the remaining 27 studies, there were a total of 2,543,483 patients, including 900,994 with prostate cancer who received ADT, 1,262,905 with prostate cancer who did not receive ADT, and 334,682 patients without prostate cancer who did not receive ADT. This analysis revealed significantly increased Hazard Ratios (HR) of 1.20 [1.11, 1.29], p < 0.00001 for dementia, HR 1.26 [1.10, 1.43], p = 0.0007 for Alzheimer's Disease, HR 1.66 [1.40, 1.97], p < 0.00001 for depression, and HR 1.57 [1.31, 1.88], p < 0.00001 for Parkinson's Disease. The risk of vascular dementia was HR 1.30 [0.97, 1.73], p < 0.00001.

CONCLUSION

Based on the analysis of the currently available evidence, it suggests that ADT significantly increases the risk of dementia, AD, PD, and depression.

How Modifiable Are Modifiable Dementia Risk Factors? A Framework for Considering the Modifiability of Dementia Risk Factors

Many risk factors for dementia, identified from observational studies, are potentially modifiable. This raises the possibility that targeting key modifiable dementia risk factors may reduce the prevalence of dementia, which has led to the development of dementia risk reduction and prevention strategies, such as intervention trials or dementia prevention guidelines. However, what has rarely been considered in the studies that inform these strategies is the extent to which modifiable dementia risk factors can (1) be identified by individuals, and (2) be readily modified by individuals. Characteristics of modifiable dementia risk factors such as readiness of identification and targeting, as well as when they should be targeted, can influence the design, or success of strategies for reducing dementia risk. This review aims to develop a framework for classifying the degree of modifiability of dementia risk factors for research studies. The extent to which these modifiable dementia risk factors could be modified by an individual seeking to reduce their dementia risk is determined, as well as the resources that might be needed for both risk factor identification and modification, and whether modification may be optimal in early-life (aged <45 years), midlife (aged 45-65 years) or late-life (aged >65 years). Finally, barriers that could influence the ability of an individual to engage in risk factor modification and, ultimately, dementia risk reduction are discussed.

Socioeconomic Status and Dementia Risk Among Intensive Care Unit Survivors: Using National Health Insurance Cohort in Korea

BACKGROUND

In aging populations, more elderly patients are going to the intensive care unit (ICU) and surviving. However, the specific factors influencing the occurrence of post-intensive care syndrome in the elderly remain uncertain.

OBJECTIVE

To investigate the association between socioeconomic status (SES) and risk of developing dementia within two years following critical care.

METHODS

This study included participants from the Korean National Health Insurance Service Cohort Database who had not been diagnosed with dementia and had been hospitalized in the ICU from 2003 to 2019. Dementia was determined using specific diagnostic codes (G30, G31) and prescription of certain medications (rivastigmine, galantamine, memantine, or donepezil). SES was categorized into low (medical aid beneficiaries) and non-low (National Health Insurance) groups. Through a 1:3 propensity score matching based on sex, age, Charlson comorbidity index, and primary diagnosis, the study included 16,780 patients. We used Cox proportional hazard models to estimate adjusted hazard ratios (HR) of dementia.

RESULTS

Patients with low SES were higher risk of developing dementia within 2 years after receiving critical care than those who were in non-low SES (HR: 1.23, 95% CI: 1.04-1.46). Specifically, patients with low SES and those in the high-income group exhibited the highest incidence rates of developing dementia within two years after receiving critical care, with rates of 3.61 (95% CI: 3.13-4.17) for low SES and 2.58 (95% CI: 2.20-3.03) for high income, respectively.

CONCLUSIONS

After discharge from critical care, compared to the non-low SES group, the low SES group was associated with an increased risk of developing dementia.

Prevalence and Determinants of Diagnosed Dementia: A Registry Linkage Study Linking Diagnosis of Dementia in the Population-Based HUNT Study to Registry Diagnosis of Dementia in Primary Care and Hospitals in Norway

Background

A timely diagnosis of dementia can be beneficial for providing good support, treatment, and care, but the diagnostic rate remains unknown and is probably low.

Objective

To determine the dementia diagnostic rate and to describe factors associated with diagnosed dementia.

Methods

This registry linkage study linked information on research-based study diagnoses of all-cause dementia and subtypes of dementias, Alzheimer's disease, and related dementias, in 1,525 participants from a cross-sectional population-based study (HUNT4 70+) to dementia registry diagnoses in both primary-care and hospital registries. Factors associated with dementia were analyzed with multiple logistic regression.

Results

Among those with research-based dementia study diagnoses in HUNT4 70+, 35.6% had a dementia registry diagnosis in the health registries. The diagnostic rate in registry diagnoses was 19.8% among home-dwellers and 66.0% among nursing home residents. Of those with a study diagnosis of Alzheimer's disease, 35.8% (95% confidence interval (CI) 32.6-39.0) had a registry diagnosis; for those with a study diagnosis of vascular dementia, the rate was 25.8% (95% CI 19.2-33.3) and for Lewy body dementias and frontotemporal dementia, the diagnosis rate was 63.0% (95% CI 48.7-75.7) and 60.0% (95% CI 43.3-75.1), respectively. Factors associated with having a registry diagnosis included dementia in the family, not being in the youngest or oldest age group, higher education, more severe cognitive decline, and greater need for help with activities of daily living.

Conclusions

Undiagnosed dementia is common, as only one-third of those with dementia are diagnosed. Diagnoses appear to be made at a late stage of dementia.

Understanding the health effects of caregiving stress: New directions in molecular aging

Dementia caregiving has been linked to multiple health risks, including infectious illness, depression, anxiety, immune dysregulation, weakened vaccine responses, slow wound healing, hypertension, cardiovascular disease, metabolic syndrome, diabetes, frailty, cognitive decline, and reduced structural and functional integrity of the brain. The sustained overproduction of proinflammatory cytokines is a key pathway behind many of these risks. However, contrasting findings suggest that some forms of caregiving may have beneficial effects, such as maintaining caregivers' health and providing a sense of meaning and purpose which, in turn, may contribute to lower rates of functional decline and mortality. The current review synthesizes these disparate literatures, identifies methodological sources of discrepancy, and integrates caregiver research with work on aging biomarkers to propose a research agenda that traces the mechanistic pathways of caregivers' health trajectories with a focus on the unique stressors facing spousal caregivers as compared to other informal caregivers. Combined with a focus on psychosocial moderators and mechanisms, studies using state-of-the-art molecular aging biomarkers such as telomere length, p16INK4a, and epigenetic age could help to reconcile mixed literature on caregiving's sequelae by determining whether and under what conditions caregiving-related experiences contribute to faster aging, in part through inflammatory biology. The biomarkers predict morbidity and mortality, and each contributes non-redundant information about age-related molecular changes -together painting a more complete picture of biological aging. Indeed, assessing changes in these biopsychosocial mechanisms over time would help to clarify the dynamic relationships between caregiving experiences, psychological states, immune function, and aging.

Associations of socioeconomic status and healthy lifestyle with incident early-onset and late-onset dementia: a prospective cohort study

BACKGROUND

Modifiable risk factor estimates are sparse for early-onset dementia incidence. This study aimed to estimate and compare the risk factor profiles of early-onset dementia and late-onset dementia, and to explore the complex relationships between socioeconomic status, lifestyles, and early-onset dementia risk.

METHODS

In this prospective cohort study, we used data from the UK Biobank for analysis of early-onset dementia and late-onset dementia. For early-onset dementia analyses, data were collected on those aged younger than 60 years without prevalent dementia at baseline. For late-onset dementia analyses, data were collected on those aged 65 years or older at the end of follow-up. Participants with missing information on socioeconomic factors were excluded. Two models were used to test associations between early-onset dementia incidence and socioeconomic status. The first model tested associations between socioeconomic status and early-onset and late-onset dementia incidence, adjusting for covariates. Participant socioeconomic status was defined using education level, income, and employment status via latent class analysis. The second model additionally included a healthy lifestyle score, which was constructed using data on smoking, alcohol consumption, physical activity, and the Healthy Diet Index. Incident early-onset dementia was defined as a dementia case diagnosed before 65 years of age. Multivariable-adjusted Cox proportional hazard regression models were used to estimate the hazard ratio (HR) for risk of dementia. We used multivariable-adjusted Cox proportional-hazard regression models to estimate the HR for risk of both early-onset dementia and late-onset dementia.

FINDINGS

Between 2007 and 2010, 257 345 individuals were included in the analysis of early-onset dementia, and 294 133 older individuals were included in the analysis of late-onset dementia. During a mean follow-up of 11·9-12·5 years, 502 early-onset dementia cases and 5768 late-onset dementia cases were documented. Risk factor profiles were typically dissimilar between early-onset dementia and late-onset dementia. For instance, the age and sex adjusted HR for low socioeconomic status (vs high) was 4·40 (95% CI 3·43-5·65) for early-onset dementia and 1·90 (1·74-2·07) for late-onset dementia, yielding a ratio of HRs of 2·32 (1·78-3·02). After adjusting for various risk factors, participants with low socioeconomic status (vs high) had increased risk for early-onset dementia (3·38, 2·61-4·37), and overall lifestyle mediated 3·2% (1·8-5·7) of the association. Individuals with both low socioeconomic status and unhealthy lifestyles had a higher risk of early-onset dementia (5·40, 3·66-7·97). No significant interaction was observed between lifestyle and socioeconomic status. The association between socioeconomic status and early-onset dementia seemed to be more pronounced in individuals with type 2 diabetes (HR 11·21, 95% CI 2·70-46·57).

INTERPRETATION

Early-onset dementia and late-onset dementia might have different risk factor profiles; although risk factors were similar, the magnitude of associations between risk factors and dementia incidence was greater for early-onset dementia. Only a small proportion of the socioeconomic inequity in dementia risk was mediated by healthy lifestyles, which indicates that measures other than healthy lifestyle promotion to improve social determinants of health are warranted.

FUNDING

The National Key Research and Development Program of China, the National Natural Science Foundation of China, the Hubei Province Science Fund for Distinguished Young Scholars, and the Fundamental Research Funds for the Central Universities.

Negative Wealth Shock and Cognitive Decline and Dementia in Middle-Aged and Older US Adults

Importance

As a financial hardship, negative wealth shock has been implicated in some adverse health outcomes. However, associations between negative wealth shock and cognitive decline and dementia have not been examined.

Objective

To investigate whether negative wealth shock was associated with cognitive decline and incident dementia among middle-aged and older US adults.

Design, Setting, and Participants

The Health and Retirement Study (HRS) is a prospective cohort study conducted biennially among US adults older than 50 years. Data from the HRS from calendar years 1996 to 2020 were analyzed from July 1 to 31, 2023. The final sample included 8082 participants with complete data of interest.

Exposures

Wealth status was quantified with questionnaires. Negative wealth shock was defined as a loss of 75% or more in total wealth over a 2-year period. Asset poverty was defined as zero or less total net wealth.

Main Outcomes and Measures

Cognitive function was assessed with the modified Telephone Interview for Cognitive Status (TICS-m). Dementia status was determined with TICS-m scores and proxy assessment.

Results

Among 8082 participants included (mean [SD] age, 63.7 [5.7] years; 4179 women [51.7%] and 3903 men [48.3%]; 1111 Black [13.7%], 6689 White [82.7%], and 282 other [3.5%]), 1441 developed incident dementia over a median follow-up time of 14 (IQR, 7-20) years. Compared with participants who had positive wealth without shock, those with negative wealth shock had accelerated cognitive decline (β coefficient, -0.014 [95% CI, -0.027 to -0.001]; P = .03) and increased risks of dementia (hazard ratio [HR], 1.27 [95% CI, 1.11-1.46]; P < .001). Higher dementia risks were also found in participants with asset poverty at baseline (HR, 1.61 [95% CI, 1.30-2.00]; P < .001). Associations were found in White participants (HR, 1.34 [95% CI, 1.14-1.58]; P < .001) and participants younger than 65 years (HR, 1.38 [95% CI, 1.13-1.68]; P = .001) but not in other races and ethnicities or those 65 years or older.

Conclusions and Relevance

In this cohort study, negative wealth shock was associated with accelerated cognitive decline and elevated risks of dementia among middle-aged and older US adults, with modifications by age and ethnicity. These findings should be confirmed by further prospective and interventional studies.

Identification of Factors in Moderate-Severe TBI Related to a Functional Decline in Cognition Decades After Injury

OBJECTIVE

To investigate whether a functional decline in cognitive activities decades after moderate-to-severe traumatic brain injury (m-sTBI) might relate to injury features and/or lifetime health factors, some of which may emerge as consequences of the injury.

DESIGN

Secondary analysis of the TBI Model Systems National Database, a prospective, multi-center, longitudinal study of patients with m-sTBI.

SETTING

TBI Model Systems Centers.

PARTICIPANTS

Included were 732 participants rated on the cognitive subscale of the Functional Independence Measure (FIM Cognitive), a metric for everyday cognitive skills, across 3 time points out to 20 years (visits at 2-, 10-, and 20-year follow-ups; N=732).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURE(S)

FIM Cognitive Scale. Injury characteristics such as timing and features pertaining to severity and health-related factors (eg, alcohol use, socioeconomic status) were examined to discriminate stable from declining participants on the FIM Cognitive Scale using logistic regression.

RESULTS

At 20 years post-injury, there was a low base rate of FIM Cognitive decline (11%, n=78), with most being stable or having meaningful improvement (89%, n=654). Older age at injury, longer duration of post-traumatic amnesia, and presence of repetitive seizures were significant predictors of FIM Cognitive decline in the final model (area under the curve=0.75), while multiple health-related factors that can represent independent co-morbidities or possible consequences of injury were not.

CONCLUSION(S)

The strongest contributors to reported functional decline in cognitive activities later-in-life were related to acute characteristics of m-sTBI and experiencing post-traumatic seizures. Future studies are needed integrating functional with performance-based cognitive assessments to affirm conclusions and identify the timeline and trajectory of cognitive decline.

Social determinants of health and cognitive function: A cross-sectional study among men without dementia

BACKGROUND

Certain age-related and medical factors have been associated with cognitive dysfunction; however, less is known regarding social determinants of health. The current study aimed to investigate associations between social determinants of health and cognitive function in a population-based sample of men without dementia.

METHODS

Data were drawn from the ongoing Geelong Osteoporosis Study (n = 536). Cognitive function was determined using the Cog-State Brief Battery. Area-based socioeconomic status (SES) was determined using the Index of Relative Socioeconomic Advantage and Disadvantage, marital status by self-report, and social support by the Multidimensional Scale of Perceived Social Support, which considers family, friends, and significant others.

RESULTS

Belonging to a higher SES group, being in a relationship (married/de-facto) and perceived social support from a significant other and friends were each associated with better overall cognitive function. In regard to the specific cognitive domains, higher SES was associated with better psychomotor function and visual learning, being in a relationship was associated with better working memory, and perceived social support from a significant other was associated with better attention and working memory, with perceived social support from friends associated with better psychomotor function. There were no associations detected between social support from family and any of the cognitive domains.

CONCLUSION

Higher SES, being in a relationship, and greater perceived social support from a significant other and friends were associated with better cognitive function. Further studies identifying underlying mechanisms linking social factors with cognition are needed to establish prevention strategies and enhance cognitive health.

The association of perceived discrimination with dementia risk in Black older adults

INTRODUCTION

Non-Hispanic Black, compared to non-Hispanic White, older adults are at increased risk for dementia. This may be due partly to greater exposure to psychosocial stressors, such as discrimination; however, few studies have examined this association.

METHODS

We examined the association of perceived discrimination (e.g., everyday, lifetime, and discrimination burden) with dementia risk in 1583 Black adults co-enrolled in the Atherosclerosis Risk in Communities (ARIC) Study and the Jackson Heart Study (JHS). Perceived discrimination (defined continuously and using tertiles) was assessed at JHS Exam 1 (2000-2004; mean age ± SD:66.2 ± 5.5) and related to dementia risk through ARIC visit 6 (2017) using covariate-adjusted Cox proportional hazards models.

RESULTS

Associations of perceived everyday, lifetime, and burden of discrimination with dementia risk were not supported in age-adjusted models or demographic- and cardiovascular health-adjusted models. Results were similar across sex, income, and education.

DISCUSSION

In this sample, associations between perceived discrimination and dementia risk were not supported.

HIGHLIGHTS

In Black older adults perceived discrimination not associated with dementia risk. Younger age and greater education linked to greater perceived discrimination. Older age and less education among factors associated with dementia risk. Factors increasing exposure to discrimination (education) are also neuroprotective.

Barriers to brain health behaviours: results from the Five Lives Brain Health Ireland Survey

Modifiable risk factors for dementia remain prevalent in Ireland. A detailed examination of barriers to risk reduction behaviours in an Irish context has heretofore been lacking. Many existing studies examining barriers to brain health behaviours fail to examine how they might vary across different modifiable risk factors. This study undertook a detailed assessment of barriers to individual risk reduction behaviours. As existing research suggests that barriers may vary across sociodemographic factors, we sought to investigate the distribution of barriers across age, gender, educational status, and household income. The Five Lives Brain Health Ireland Survey is a cross-sectional survey that was distributed online amongst a non-patient population. The survey captured the following: (1) Sociodemographic factors; (2) Barriers to brain health behaviours; (3) Exposure to, and knowledge of, modifiable risk factors for dementia, namely diet, social interaction, exercise, hypertension, sleep, current low mood/depression, current smoking, alcohol consumption, cognitive stimulation, hearing impairment, diabetes, air pollution, and head injury; (4) Participants' perceptions regarding potential for dementia prevention, and risk reduction. Lack of motivation was the most prevalent barrier to consuming a healthy diet (64%, n = 213), physical activity (77.7%, n = 167), smoking cessation (68%, n = 85), and moderation of alcohol intake (56.3%, n = 67). Practical factors were the most prevalent barriers to addressing low mood (56.5%, n = 87), air pollution (30.1%, n = 58), hearing impairment (63.8%, n = 44), diabetes (11.1%, n = 5), and head injury (80%, n = 8). Emotional factors were the most prevalent barriers to engaging in mentally stimulating activity (56.9%, n = 66), social activity (54.9%, n = 302), and good sleep (70.1%, n = 129). Lack of knowledge was the most prevalent barrier to hypertension control (14.4%, n = 29). Distribution of barriers varied across age, gender, educational status, and household income. This study investigated barriers to lifestyle change to improve brain health in an Irish sample of adults aged 50 and above. Detailed subtyping of barriers, as well as examination of differences according to age, gender, education, and income were undertaken. The heterogeneity of barriers to brain health behaviours revealed in this study highlights the necessity to tailor public health interventions to their target population, taking into account the gender, age, educational status, and income of recipients.

Demoralization syndrome and its impact factors among cancer patients in China

PURPOSE

This study aimed to investigate the status of demoralization syndrome among cancer patients and explore the key factors influencing demoralization syndrome.

METHOD

Cross-sectional study design of cancer patients in Xiamen, China. Patients completed the Mandarin version of the Perceived Social Support Scale, Patient-Reported Outcome Measures, The Anderson Symptom Inventory, and the Demoralization Scale.

FINDINGS

187/199 (94%) of patients completed questionnaires. This study found that almost half of the cancer patients in Xiamen, China experience moderate to high levels of demoralization syndrome. Furthermore, the findings indicated that the family residence (Large Urban: b = 2.73, p = 0.02), average monthly income (b=-3.05, p = 0.03), source of income, religiousness (b = 1.37, p = 0.04) and financial toxicity (b = 3.3, p < 0.001), and social support (b = 1.02; p < 0.001) are the influencing factors of cancer patients' demoralization syndrome.

CONCLUSION

These findings emphasize the importance of addressing psychological distress and providing adequate social and financial support for cancer patients to maintain their morale and overall well-being.

Racial, ethnic and neighborhood socioeconomic differences in incidence of dementia: A regional retrospective cohort study

BACKGROUND

Evidence on the effects of neighborhood socioeconomic disadvantage on dementia risk in racially and ethically diverse populations is limited. Our objective was to evaluate the relative extent to which neighborhood disadvantage accounts for racial/ethnic variation in dementia incidence rates. Secondarily, we evaluated the spatial relationship between neighborhood disadvantage and dementia risk.

METHODS

In this retrospective study using electronic health records (EHR) at two regional health systems in Northeast Ohio, participants included 253,421 patients aged >60 years who had an outpatient primary care visit between January 1, 2005 and December 31, 2015. The date of the first qualifying visit served as the study baseline. Cumulative incidence of composite dementia outcome, defined as EHR-documented dementia diagnosis or dementia-related death, stratified by neighborhood socioeconomic deprivation (as measured by Area Deprivation Index) was determined by competing-risk regression analysis, with non-dementia-related death as the competing risk. Fine-Gray sub-distribution hazard ratios were determined for neighborhood socioeconomic deprivation, race/ethnicity, and clinical risk factors. The degree to which neighborhood socioeconomic position accounted for racial/ethnic disparities in the incidence of composite dementia outcome was evaluated via mediation analysis with Poisson rate models.

RESULTS

Increasing neighborhood disadvantage was associated with increased risk of EHR-documented dementia diagnosis or dementia-related death (most vs. least disadvantaged ADI quintile HR = 1.76, 95% confidence interval = 1.69-1.84) after adjusting for age and sex. The effect of neighborhood disadvantage on this composite dementia outcome remained after accounting for known medical risk factors of dementia. Mediation analysis indicated that neighborhood disadvantage accounted for 34% and 29% of the elevated risk for composite dementia outcome in Hispanic and Black patients compared to White patients, respectively.

CONCLUSION

Neighborhood disadvantage is related to the risk of EHR-documented dementia diagnosis or dementia-related death and accounts for a portion of racial/ethnic differences in dementia burden, even after adjustment for clinically important confounders.

Exploring the bidirectional causal link between household income status and genetic susceptibility to neurological diseases: findings from a Mendelian randomization study

Objectives

Observational studies have revealed that socioeconomic status is associated with neurological disorders and aging. However, the potential causal effect between the two remains unclear. We therefore aimed to investigate the causal relationship between household income status and genetic susceptibility to neurological diseases using a bidirectional Mendelian randomization (MR) study.

Methods

An MR study was conducted on a large-sample cohort of the European population pulled from a publicly available genome-wide association study dataset, using a random-effects inverse-variance weighting model as the main standard. MR-Egger regression, weighted median, and maximum likelihood estimation were also performed concurrently as supplements. A sensitivity analysis, consisting of a heterogeneity test and horizontal pleiotropy test, was performed using Cochran's Q, MR-Egger intercept, and MR-PRESSO tests to ensure the reliability of the conclusion.

Results

The results suggested that higher household income tended to lower the risk of genetic susceptibility to Alzheimer's disease (odds ratio [OR]: 0.740, 95% confidence interval [CI] = 0.559-0.980, p-value = 0.036) and ischemic stroke (OR: 0.801, 95% CI = 0.662-0.968, p-value = 0.022). By contrast, higher household income tended to increase the risk of genetic susceptibility to Parkinson's disease (OR: 2.605, 95% CI = 1.413-4.802, p-value = 0.002). No associations were evident for intracranial hemorrhage (OR: 1.002, 95% CI = 0.607-1.653, p-value = 0.993), cerebral aneurysm (OR: 0.597, 95% CI = 0.243-1.465, p-value = 0.260), subarachnoid hemorrhage (OR: 1.474, 95% CI = 0.699-3.110, p-value = 0.308), or epilepsy (OR: 1.029, 95% CI = 0.662-1.600, p-value = 0.899). The reverse MR study suggested no reverse causal relationship between neurological disorders and household income status. A sensitivity analysis verified the reliability of the results.

Conclusion

Our results revealed that the populations with a superior household income exhibit an increased predisposition of genetic susceptibility to Parkinson's Disease, while demonstrating a potential decreased genetic susceptibility to ischemic stroke and Alzheimer's disease.

Social and spatial inequalities in healthcare use among people living with dementia in England (2002-2016)

OBJECTIVES

Healthcare services for people living with dementia (PLWD) are stretched, and government promises of increased funding remain undelivered. With the UK dementia population to surpass 1 million by 2024, and dementia care costs predicted to almost treble by 2040, it is essential we understand differences in healthcare use among PLWD. This study aimed to explore social and spatial variations in healthcare use among people diagnosed with dementia (2002-2016).

METHODS

Data were derived from Electronic Health Records of Clinical Practice Research Datalink GP patients in England (n = 142,302). To standardise healthcare contacts, rates of healthcare contacts per year were calculated for three primary (GP observations and medications) and three secondary healthcare types [Accident & Emergency (A&E) attendances and, emergency and elective hospital admissions]. Fully-adjusted generalised linear regression models were used to identify healthcare use variation by social and spatial groups. Twelve models were generated, one for each healthcare type in early- and late-onset populations separately.

RESULTS

This study highlights numerous social and spatial variations in healthcare use among PLWD. Among PLWD, several groups tended to have healthcare service use more closely associated with negative outcomes, including a greater likelihood of A&E attendances and emergency and elective hospital admissions. These groups include: men, people from White ethnicity groups and people from more deprived and rural areas.

CONCLUSIONS

Systemic and social measures are needed to reduce variations in healthcare use inequalities in PWLD. These include greater healthcare continuity, health checks and medicines reviews, culturally appropriate services, better and more accessible treatment and improved infrastructure.

Global association of greenness exposure with risk of nervous system disease: A systematic review and meta-analysis

Nervous system disease (NSD) is a global health burden with increasing prevalence in the last 30 years. There is evidence that greenness can improve nervous system health through a variety of mechanisms; however, the evidence is inconsistent. In the present systematic review and meta-analysis, we examined the relationship between greenness exposure and NSD outcomes. Studies on the relationship between greenness and NSD health outcomes published till July 2022 were searched in PubMed, Cochrane, Embase, Scopus, and Web of Science. In addition, we searched the cited literature and updated our search on Jan 20, 2023, to identify any new studies. We included human epidemiological studies that assess the association of greenness exposure with the risk of NSD. Greenness exposure was measured using NDVI (the normalized difference vegetation index) and the outcome was the mortality or morbidity of NSD. The pooled relative risks (RRs) were estimated using a random effects model. Of 2059 identified studies, 15 studies were included in our quantitative evaluation, in which 11 studies found a significant inverse relationship between the risk of NSD mortality or incidence/prevalence and an increase in surrounding greenness. The pooled RRs for cerebrovascular diseases (CBVD), neurodegenerative diseases (ND), and stroke mortality were 0.98 (95 % CI: 0.97, 1.00), 0.98 (95 % CI: 0.98, 0.99), and 0.96 (95 % CI: 0.93, 1.00), respectively. The pooled RRs for PD incidence and stroke prevalence/incidence were 0.89 (95 % CI: 0.78, 1.02) and 0.98 (95 % CI: 0.97, 0.99), respectively. The confidence of evidence for ND mortality, stroke mortality, and stroke prevalence/incidence was downgraded to "low", while CBVD mortality and PD incidence were downgraded to "very low" due to inconsistency. We found no evidence of publication bias and the sensitivity analysis results of all subgroups are robust except for the stroke mortality subgroup. This is the first comprehensive meta-analysis of greenness exposure and NSD outcomes in which an inverse relationship was observed. It is necessary to conduct further research to ascertain the role greenness exposure plays in various NSDs and the management of greenness should be considered a public health strategy.

Socioeconomic status as a risk factor for motoric cognitive risk syndrome in a community-dwelling population: A longitudinal observational study

BACKGROUND

Motoric cognitive risk (MCR) is a syndrome characterised by measured slow gait speed and self-reported cognitive complaints. MCR is a high-risk state for adverse health outcomes in older adults, particularly cognitive impairment and dementia. Previous studies have identified risk factors for MCR, but the effect of socioeconomic status has, to date, been insufficiently examined. This study explored the association between MCR and socioeconomic status, as determined by occupational social class and years of education.

METHODS

Some 692 community-based adults of the Lothian Birth Cohort 1936 (LBC1936), aged 70 years at baseline, were followed up after 6 years and classified into non-MCR and MCR groups. We applied logistic regression analyses adjusting for demographic, lifestyle, and health covariates to investigate the association between MCR and years of education and occupational social class, categorised into manual versus non-manual occupations.

RESULTS

MCR prevalence at age 76 years was 5.6% (95% CI 4.0-7.6). After multivariate adjustment, participants of lower socioeconomic status (manual occupation) had a greater than three-fold increased likelihood of MCR (adjusted odds ratio 3.55, 95% CI 1.46-8.74; p = 0.005) compared with those of higher socioeconomic status (non-manual occupation).

CONCLUSIONS

Working in a manual job earlier in life triples the risk of MCR later in life, regardless of education. Unravelling this association will likely reveal important pathophysiological mechanisms underlying MCR and may unearth modifiable risk factors which could be targeted to reduce the incidence of MCR and, ultimately, dementia. Policy and healthcare practice addressing dementia risks such as MCR in their social context and early in the lifecourse could be effective strategies for reducing health inequalities in older age.

Knowledge and Attitudes towards Dementia among the General Public in Singapore: A Comparative Analysis

INTRODUCTION

This paper provides a summary of findings on the public's knowledge and attitudes towards dementia. We aim to investigate if the attitudes of Singaporeans towards dementia have changed over the years by adopting a questionnaire used in a similar study in 2012.

METHODS

A cross-sectional, descriptive study was conducted through the dissemination of an existing, online questionnaire to participants above 16 years of age. Out of 1,500 subjects, results from 1,373 participants were analysed. Descriptive statistics were used to analyse and compare results from the 2012 study while a latent class analysis was performed to understand the categories of study participants based on varying levels of attitudes, knowledge and stigma.

RESULTS

The mean age of study participants was 43.8 (SD = 15.7). Majority of the participants were females (76.5%), between 51 and 60 years of age (29.6%) and belonged to the Chinese ethnic group (77.8%). Results demonstrated that there were significant differences in attitudes towards dementia between 2012 and 2021. There was a 70.2% improvement in stigma-associated attitudes and an increase in correct responses to 4 out of 5 questions in the knowledge section.

CONCLUSION

Findings of this study suggest that the general public has a better knowledge and more positive attitude towards dementia. This could have been attributed to higher literacy levels of the current study population and effectiveness of established outreach initiatives in Singapore. However, further research with a more balanced representation of ethnic and cultural groups would offer more comprehensive insights into dementia health literacy.

The associations of socioeconomic status with incident dementia and Alzheimer's disease are modified by leucocyte telomere length: a population-based cohort study

Socio-economic status (SES) and biological aging are risk factors for dementia, including Alzheimer's disease, however, it is less clear if the associations with SES vary sufficiently across different biological age strata. We used data from 331,066 UK Biobank participants aged 38-73 with mean follow-up of 12 years to examine if associations between SES (assessed by educational attainment, employment status and household income) and dementia and Alzheimer's disease are modified by biological age (assessed by leucocyte telomere length: LTL). Diagnosis of events was ascertained through hospital admissions data. Cox regressions were used to estimate hazard ratios [HRs]. A consistent dose-response relationship was found, with participants in low SES and shorter LTL strata (double-exposed group) reporting 3.28 (95% confidence interval [CI] 2.57-4.20) and 3.44 (95% CI 2.35-5.04) times higher risks of incident dementia and Alzheimer's disease respectively, compared to those of high SES and longer LTL (least-exposed group). Of interest is a synergistic interaction between SES and LTL to increase risk of dementia (RERI 0.57, 95% CI 0.07-1.06) and Alzheimer's disease (RERI 0.79, 95% CI 0.02-1.56). Our findings that SES and biological age (LTL) are synergistic risk factors of dementia and Alzheimer's disease may suggest the need to target interventions among vulnerable sub-groups.

The Association between Primary Care Practices' Structural Capabilities and Hospitalizations among Persons Living with Dementia

Background: Persons living with dementia (PLWD) are more likely to be hospitalized than individuals without dementia. Little is known about key features (i.e., structural capabilities) in primary care practices where PLWD receive care. This study assessed the relationship between structural capabilities (i.e., care coordination, community integration, and reminder systems) and hospitalizations among PLWD. Methods: We conducted a secondary analysis of cross-sectional data from 5001 PLWD in 192 practices and used three datasets: nurse practitioner surveys, Medicare claims, and Minimum Data Set. Using generalized estimating equations, we evaluated the association between structural capabilities and hospitalizations. Results: PLWD who received care from practices with care coordination were less likely to have hospitalizations (OR = 0.62, p < .05). No statistically significant associations were observed between community integration and reminder systems and hospitalizations. Conclusion: Primary care practices need to tailor structural capabilities to address the needs of PLWD to reduce hospitalizations.

Mediterranean diet and structural neuroimaging biomarkers of Alzheimer's and cerebrovascular disease: A systematic review

Previous studies have demonstrated an association between adherence to the Mediterranean diet (MedDiet) and better cognitive performance, lower incidence of dementia and lower Alzheimer's disease biomarker burden. The aim of this systematic review was to evaluate the evidence base for MedDiet associations with hippocampal volume and white matter hyperintensity volume (WMHV). We searched systematically for studies reporting on MedDiet and hippocampal volume or WMHV in MedLine, EMBASE, CINAHL and PsycInfo. Searches were initially carried out on 21st July 2021 with final searches run on 23rd November 2022. Risk of bias was assessed using the NIH Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Of an initial 112 papers identified, seven papers were eligible for inclusion in the review reporting on 21,933 participants. Four studies reported on hippocampal volume, with inconclusive or no associations seen with MedDiet adherence. Two studies found a significant association between higher MedDiet adherence and lower WMHV, while two other studies found no significant associations. Overall these results highlight a gap in our knowledge about the associations between the MedDiet and AD and cerebrovascular related structural neuroimaging findings.

Sex difference in the associations of socioeconomic status, cognitive function and brain volume with dementia in old adults: Findings from the OASIS study

Background

Sex differences in the association of cognitive function and imaging measures with dementia have not been fully investigated while sex-based investigation of dementia has been discussed. Understanding sex differences in the dementia-related socioeconomic, cognitive, and imaging measurements is important for uncovering sex-related pathways to dementia and facilitating early diagnosis, family planning, and cost control.

Methods

We selected data from the Open Access Series of Imaging Studies with longitudinal measurements of brain volumes on 150 individuals aged 60 to 96 years. Dementia status was determined using the Clinical Dementia Rating (CDR) scale, and Alzheimer's disease was diagnosed as a CDR of ≥ 0.5. Generalized estimating equation models were used to estimate the associations of socioeconomic, cognitive and imaging factors with dementia in men and women.

Results

Lower education affected dementia more in women than in men. Age, education, Mini-Mental State Examination (MMSE), and normalized whole-brain volume (nWBV) were associated with dementia in women whereas only MMSE and nWBV were associated with dementia in men. Lower socioeconomic status was associated with a reduced estimated total intracranial volume in men, but not in women. Ageing and lower MMSE scores were associated with reduced nWBV in both men and women.

Conclusions

The association between education and prevalence of dementia differs in men and women. Women may have more risk factors for dementia than men.

Observational studies in Alzheimer disease: bridging preclinical studies and clinical trials

Recent high-profile failures of Alzheimer disease treatments at the clinical trial stage have led to renewed efforts to identify and test novel interventions for Alzheimer disease and related dementias (ADRD). In this Perspective, we highlight the importance of including well-designed observational studies as part of these efforts. Observational research is an important cornerstone for gathering evidence on risk factors and causes of ADRD; this evidence can then be combined with data from preclinical studies and randomized controlled trials to inform the development of effective interventions. Observational study designs can be particularly beneficial for hypothesis generation, posing questions that are unethical or impractical for a trial setting, studying life-course associations, research in populations typically not included in trials, and public health surveillance. Here, we discuss each of these situations in the specific context of ADRD research. We also highlight novel approaches to enhance causal inference and provide a timely discussion on how observational epidemiological studies help provide a bridge between preclinical studies and successful interventions for ADRD.

A review on the application of the exposome paradigm to unveil the environmental determinants of age-related diseases

Age-related diseases account for almost half of all diseases among adults worldwide, and their incidence is substantially affected by the exposome, which is the sum of all exogenous and endogenous environmental exposures and the human body’s response to these exposures throughout the entire lifespan. Herein, we perform a comprehensive review of the epidemiological literature to determine the key elements of the exposome that affect the development of age-related diseases and the roles of aging hallmarks in this process. We find that most exposure assessments in previous aging studies have used a reductionist approach, whereby the effect of only a single environmental factor or a specific class of environmental factors on the development of age-related diseases has been examined. As such, there is a lack of a holistic and unbiased understanding of the effect of multiple environmental factors on the development of age-related diseases. To address this, we propose several research strategies based on an exposomic framework that could advance our understanding—in particular, from a mechanistic perspective—of how environmental factors affect the development of age-related diseases. We discuss the statistical methods and other methods that have been used in exposome-wide association studies, with a particular focus on multiomics technologies. We also address future challenges and opportunities in the realm of multidisciplinary approaches and genome–exposome epidemiology. Furthermore, we provide perspectives on precise public health services for vulnerable populations, public communications, the integration of risk exposure information, and the bench-to-bedside translation of research on age-related diseases.

Prevalence and predictors of Motoric Cognitive Risk syndrome in a community-dwelling older Scottish population: A longitudinal observational study

OBJECTIVES

Motoric Cognitive Risk (MCR) is a gait-based predementia syndrome that is easy to measure and prognostic of dementia and falls. We aimed to examine the prevalence and risk factors for MCR, and assess its overlap with Mild Cognitive Impairment, Prefrailty, and Frailty, in a cohort of older Scottish adults without dementia.

METHODS

In this longitudinal prospective study, we classified 690 participants (mean [SD] age 76.3 [0.8] years; wave 3) of the Lothian Birth Cohort 1936 (LBC1936) into non-MCR or MCR groups. We examined their baseline (age 69.5 [0.8] years; wave 1) risk factors for MCR at waves 3, 4, and 5 (6, 9, and 12 years later respectively).

RESULTS

MCR prevalence rate ranged from 5.3% to 5.7% across the three waves. The presence of MCR was associated with older baseline age (6 and 9 years later), lower occupational socioeconomic status (6 years later), and worse scores in a range of tests of executive function (6, 9 and 12 years later). Approximately 46% of the MCR group also had Mild Cognitive Impairment, and almost everyone in the MCR group had either Prefrailty or Frailty.

CONCLUSIONS

The prevalence of MCR in this Scottish cohort is lower than the pooled global average, possibly reflecting the general good health of the LBC cohort. However, it is higher than the prevalence in two neighbouring countries' cohorts, which may reflect the younger average ages of those cohorts. Future LBC1936 research should assess the risk factors associated with MCR to validate previous findings and analyse novel predictive factors, particularly socioeconomic status.

Prevalence and correlates of suspected dementia in older adults receiving primary healthcare in Wuhan, China: A multicenter cross-sectional survey

Background

Integrating the management of dementia into primary healthcare is a cost-effective way to reduce the burden of dementia but the clinical epidemiology of dementia in primary healthcare settings remains unclear. This study investigated the prevalence and correlates of suspected dementia in Chinese older adults receiving primary healthcare.

Methods

In this multicenter cross-sectional survey, a total of 773 older adults (≥65 years) were consecutively recruited from seven urban and six rural primary care clinics in Wuhan, China, and interviewed with the validated Chinese version of the Brief Community Screening Instrument for Dementia (BCSI-D). Participants with suspected dementia were those who were screened positive on the BCSI-D.

Results

The prevalence of suspected dementia in older primary healthcare adults was 26.8%. Factors significantly associated with suspected dementia were female sex (OR = 1.95, P < 0.001), age-group of 75+ (OR = 1.68, P = 0.004), poor financial status (OR = 4.79, P < 0.001), rural residence (OR = 1.47, P = 0.032), no regular physical exercise (OR = 1.74, P = 0.002), and stroke and other cerebrovascular diseases (OR = 1.97, P = 0.015).

Conclusions

Chinese older adults receiving primary healthcare are at high risk of suspected dementia. Screening and intervention efforts for dementia in primary healthcare settings may be more useful to target older adults who are women, are 75 years and above, have poor economic status, are rural residents, have no exercise habit, and suffer from cerebrovascular diseases.

Neurovascular Dysfunction in Diverse Communities With Health Disparities-Contributions to Dementia and Alzheimer's Disease

Alzheimer's disease and related dementias (ADRD) are an expanding worldwide crisis. In the absence of scientific breakthroughs, the global prevalence of ADRD will continue to increase as more people are living longer. Racial or ethnic minority groups have an increased risk and incidence of ADRD and have often been neglected by the scientific research community. There is mounting evidence that vascular insults in the brain can initiate a series of biological events leading to neurodegeneration, cognitive impairment, and ADRD. We are a group of researchers interested in developing and expanding ADRD research, with an emphasis on vascular contributions to dementia, to serve our local diverse community. Toward this goal, the primary objective of this review was to investigate and better understand health disparities in Alabama and the contributions of the social determinants of health to those disparities, particularly in the context of vascular dysfunction in ADRD. Here, we explain the neurovascular dysfunction associated with Alzheimer's disease (AD) as well as the intrinsic and extrinsic risk factors contributing to dysfunction of the neurovascular unit (NVU). Next, we ascertain ethnoregional health disparities of individuals living in Alabama, as well as relevant vascular risk factors linked to AD. We also discuss current pharmaceutical and non-pharmaceutical treatment options for neurovascular dysfunction, mild cognitive impairment (MCI) and AD, including relevant studies and ongoing clinical trials. Overall, individuals in Alabama are adversely affected by social and structural determinants of health leading to health disparities, driven by rurality, ethnic minority status, and lower socioeconomic status (SES). In general, these communities have limited access to healthcare and healthy food and other amenities resulting in decreased opportunities for early diagnosis of and pharmaceutical treatments for ADRD. Although this review is focused on the current state of health disparities of ADRD patients in Alabama, future studies must include diversity of race, ethnicity, and region to best be able to treat all individuals affected by ADRD.

Sex differences in the association between cardiovascular diseases and dementia subtypes: a prospective analysis of 464,616 UK Biobank participants

BACKGROUND

Whether the association of cardiovascular diseases (CVDs) with dementia differs by sex remains unclear, and the role of socioeconomic, lifestyle, genetic, and medical factors in their association is unknown.

METHODS

We used data from the UK Biobank, a population-based cohort study of 502,649 individuals. We used Cox proportional hazards models to estimate sex-specific hazard ratios (HRs) and 95% confidence intervals (CI), and women-to-men ratio of HRs (RHR) for the association between CVD (coronary heart diseases (CHD), stroke, and heart failure) and incident dementia (all-cause dementia, Alzheimer's Disease (AD), and vascular dementia (VD)). The moderator roles of socioeconomic (education, income), lifestyle (smoking, BMI, leisure activities, and physical activity), genetic factors (APOE allele status), and medical history were also analyzed.

RESULTS

Compared to people who did not experience a CVD event, the HRs (95%CI) between CVD and all-cause dementia were higher in women compared to men, with an RHR (Female/Male) of 1.20 (1.13, 1.28). Specifically, the HRs for AD were higher in women with CHD and heart failure compared to men, with an RHR (95%CI) of 1.63 (1.39, 1.91) and 1.32 (1.07, 1.62) respectively. The HRs for VD were higher in men with heart failure than women, with RHR (95%CI) of 0.73 (0.57, 0.93). An interaction effect was observed between socioeconomic, lifestyle, genetic factors, and medical history in the sex-specific association between CVD and dementia.

CONCLUSION

Women with CVD were 1.5 times more likely to experience AD than men, while had 15% lower risk of having VD than men.

Anthocyanin as a therapeutic in Alzheimer's disease: A systematic review of preclinical evidences

BACKGROUND

The aim of this systematic review is to ponder the possible mechanism of action of anthocyanin in Alzheimer's disease (AD), to prompt the development of anthocyanin-based dietary supplementation or therapeutic intervention for AD and to explore the natural sources of anthocyanins.

METHODS

Electronic bibliographic databases such as PubMed, ScienceDirect, Proquest, DOAJ, Scopus, and Google Scholar were searched for preclinical studies probing the efficacy of anthocyanin on AD. The search strategy included no time limit, but was restricted to English. The review protocol is registered on PROSPERO, registration no. CRD42021272972. The systematic review followed the PICO approach for inclusion of reports. All the reports were appraised for risk of bias using the SYRCLE's RoB tool.

RESULTS

Bibliographic details of the article, animal strain/weight/age, induction model, anthocyanin source, type of anthocyanin, dose, route of administration, duration, and the outcome measures were extracted from 12 retrieved reports explicitly. The implication of food-based anthocyanin in acute and long-term cognition and Aβ mediated neurodegeneration appears alluring. Majority of the studies comprehended in this review had moderate methodological quality.

DISCUSSION

Efficacy of anthocyanin in alleviating oxidative stress, reactive astrogliosis, cholinergic dysfunction, apoptosis, synaptotoxicity, neuroinflammation, tau hyperphosphorylation, dysregulated membrane potential, neuronal extracellular calcium, dysfunctional amyloidogenic pathway, and cognitive deficits in various rodent models of AD is manifested compositely in 12 studies.

Annual Incidence of Dementia from 2003 to 2018 in Metropolitan Seoul, Korea: A Population-Based Study

National dementia plans were applied in dementia support centers established in Seoul, Korea between 2007 and 2009. However, the annual incidence rates of dementia in Seoul have not been reported. We investigated this annual incidence and the characteristics of incident cases from 2003 to 2018. The customized research database of the Korean National Health Insurance Services was used. The annual crude and age-standardized incidence of dementia patients and their characteristics were analyzed. This study analyzed 108,596 incident dementia cases aged ≥60 years. The incidence rate increased from 2003 to 2011, including a rapid increment from 2007 to 2011. From 2011 to 2018, the crude (age-standardized) incidence per 105 person-years decreased from 641.51 (577.12) to 448.26 (361.23). The proportion of incident dementia cases was highest in the highest income group every year. However, the proportion of incident dementia cases in the lowest income group increased from 10.4% in 2003 to 25.8% in 2011. The annual incidence rate of dementia showed a sharp increase immediately after 2007, the year dementia support centers began to be introduced, and then stabilized after 2011. The characteristics of incident dementia cases have changed, including the proportion in the low-income group.

Association between depression and the risk of Alzheimer's disease using the Korean National Health Insurance Service-Elderly Cohort

In this cohort study, we assessed the association between depression and the risk of Alzheimer’s disease from data obtained from the 2002 to 2013 Korean National Health Insurance Service-Elderly Cohort Database, which accounts for 10% of the South Korean population aged > 60 years. A total 518,466 patients were included in the analysis and followed up, unless they were excluded due to death or migration. Patients who sought treatment for depression or dementia within 1 year of the washout period and who were diagnosed with dementia within the 1-year period of the diagnosis of depression were excluded from the study. The risk of dementia was analysed using Cox proportional hazards models. Patients with a history of depression during the follow-up period were at a higher risk of Alzheimer’s disease than those without a history of depression (HR 3.35, CI 3.27–3.42). The severe-depression group exhibited the highest risk of Alzheimer’s disease (HR 4.41, CI 4.04–4.81), while the mild-depression group exhibited a relatively lower risk of Alzheimer’s disease (HR 3.31, CI 3.16–3.47). The risk of Alzheimer’s disease was associated with depression history and an increased severity of depression increased the risk of Alzheimer’s disease.

Blood Pressure Levels and Risks of Dementia: a Nationwide Study of 4.5 Million People

There are inconsistent results on the impacts of controlling blood pressure (BP) on the risk of dementia. We investigated the association between BP and risk of dementia subtypes by antihypertensive treatment and comorbidities. Using the Korean National Health Insurance Service-Health Screening Database from 2009 to 2012, a total of 4 522 447 adults aged 60+ years without a history of dementia were analyzed and followed up for a mean of 5.4 years. Individuals were classified according to their baseline systolic BP (SBP) and diastolic BP; SBP 130 to <140 mm Hg and diastolic BP 80 to <90 mm Hg were used as reference groups. The risk of overall dementia and probable Alzheimer disease was significantly higher in the SBP≥160 and lower SBP groups. These U-shaped associations were consistent regardless of antihypertensive use or comorbidities. The risk of probable vascular dementia (VaD) was not higher among lower SBP groups and increased gradually as SBP increased. Although there was a linear association between SBP and the risk of probable VaD in individuals not taking antihypertensives or without comorbidities, there was a U-shaped association in individuals taking antihypertensives or with comorbidities. Patterns of association between diastolic BP and risk of probable Alzheimer disease or probable VaD were similar to those with SBP, except for the risk of probable VaD in individuals taking antihypertensives. In conclusion, risks of probable Alzheimer disease and probable VaD were different among lower BP groups. Although the risk of dementia appears higher in people with lower BP receiving antihypertensives, this finding may be affected by comorbidities.

Socioeconomic Position and Late-Onset Dementia: A Nationwide Register-Based Study

OBJECTIVES

Previous research on the association between socioeconomic position (SEP) and dementia has not sufficiently accounted for the complex relationship between education and occupation. We investigated the independent and joint effects of educational attainment and occupation-based SEP on dementia.

METHODS

We used register-based information about educational attainment, occupation-based SEP, and dementia from 1,210,720 individuals. Information about cognitive ability at conscription was available for a subsample of men.

RESULTS

When mutually adjusted, lower educational attainment and occupation-based SEP were associated with higher dementia risk in a dose-response manner. Higher occupation-based SEP partly mitigated the higher dementia risk associated with lower educational attainment. After adjusting for cognitive ability in a subgroup of men, only unskilled work was associated with higher dementia risk.

DISCUSSION

Occupation-based SEP is independently associated with dementia and may mitigate the higher dementia risk associated with short education. Future research should elucidate the mechanisms underlying social inequality in dementia.

Predictors of Hospitalization for Manic Episode in Alzheimer's Dementia: Inputs From an Inpatient Case-Control Study

Objectives The correlates of manic episodes in dementia have not been systematically studied. The primary goal of our study is to compare the sociodemographic characteristics and psychiatric comorbidities in Alzheimer's dementia (AD) inpatients with manic episodes versus without manic episodes, and to evaluate the demographic predictors and risk factors for manic episodes in AD inpatients. Methods We conducted a case-control study using the Nationwide Inpatient Sample of 34,285 AD patients (age ≥60 years). Subsequently, the cases i.e., AD inpatients with a manic episode (N = 1,035) and the controls (without a manic episode, N = 1,035), were extracted using propensity-score matching based on age. The cases did not have a past psychiatric history of bipolar disorders. We used the logistic regression model to evaluate the odds ratio (OR) of association between pre-existing psychiatric comorbidities and manic episodes and evaluate the demographic predictors of manic episodes in AD inpatients. Results A higher proportion of AD inpatients with manic episodes were females (63.8%), whites (85.2%), and from low-income families below the 50th percentile (63%). Females were more likely to be hospitalized for manic episodes (OR 1.33; 95% CI 1.09-1.64) than males. AD inpatients with manic episodes had a higher risk of presenting with suicidal behaviors (OR 1.88; 95% CI 1.23-2.86). A significantly higher proportion of AD inpatients with manic episodes had comorbid tobacco use (5.3% vs. 3.4%) and cannabis use (1.4% vs. 0%) compared to those without manic episodes. Conclusion Females with AD had a greater risk of being hospitalized for manic episodes. These patients have an 88% higher risk of suicidal behaviors during the manic presentation and have comorbid tobacco and cannabis use. Early diagnosis and management of manic episodes in at-risk AD patients are important to improve the quality of life (QoL) and outcomes.

Medical and Social Determinants of Brain Health and Dementia in a Multicultural Community Cohort of Older Adults

BACKGROUND

Socioeconomic status (SES), race, ethnicity, and medical comorbidities may contribute to Alzheimer's disease and related disorders (ADRD) health disparities.

OBJECTIVE

Analyze effects of social and medical determinants on cognition in 374 multicultural older adults participating in a community-based dementia screening program.

METHODS

We used the Montreal Cognitive Assessment (MoCA) and AD8 as measures of cognition, and a 3-way race/ethnicity variable (White, African American, Hispanic) and SES (Hollingshead index) as predictors. Potential contributors to health disparities included: age, sex, education, total medical comorbidities, health self-ratings, and depression. We applied K-means cluster analyses to study medical and social dimension effects on cognitive outcomes.

RESULTS

African Americans and Hispanics had lower SES status and cognitive performance compared with similarly aged Whites. We defined three clusters based on age and SES. Cluster #1 and #3 differed by SES but not age, while cluster #2 was younger with midlevel SES. Cluster #1 experienced the worse health outcomes while cluster #3 had the best health outcomes. Within each cluster, White participants had higher SES and better health outcomes, African Americans had the worst physical performance, and Hispanics had the most depressive symptoms. In cross-cluster comparisons, higher SES led to better health outcomes for all participants.

CONCLUSION

SES may contribute to disparities in access to healthcare services, while race and ethnicity may contribute to disparities in the quality and extent of services received. Our study highlights the need to critically address potential interactions between race, ethnicity, and SES which may better explain disparities in ADRD health outcomes.